Forbes 2016 World’s Billionaires: Mukesh Ambani of India at Number 36 and Bill Gates at Number 1

Volatile stock markets, cratering oil prices and a stronger dollar led to a dynamic reshuffling of wealth around the globe and a drop in ten-figure fortunes for the first time since 2009. For our 30th annual guide to the world’s richest, we found 1,810 billionaires, down from a record 1,826 a year ago. Their aggregate net worth was $6.48 trillion, $570 billion less than last year. It was also the first time since 2010 that the average net worth of a billionaire dropped – it is now $3.6 billion, $300 million less than last year.

Behind these figures is a story of huge upheaval, as 221 people fell off the list, while 198 newcomers joined the ranks; another 29 people from 2015 died while 29 who’d previously fallen off climbed back on. Of those who were billionaires both years, 892 are poorer while 501 added to their fortunes.

The reshuffling starts at the top. Only 2 people in the top 20 managed to hold onto their ranks. Bill Gates remains the richest person in the world with a net worth of $75 billion, despite being $4.2 billion poorer than a year ago. He has been No. 1 one for 3 years in a row and topped the list 17 out of 22 years. (In the 30 years FORBES has tracked global wealth, only 5 people have held the title of richest person on planet; 3 of those 5 still rank among the 4 richest in the world including Warren Buffett and Carlos Slim.) Also holding steady is Buffett at No. 3. Zara’s Amancio Ortega moves up to No. 2 for the first time, displacing Mexico’s Carlos Slim, who slips to No. 4. Slim’s fortune fell $27.1 billion to $50 billion in the past year, as shares of his telecom business América Móvil tumbled.

FacebookFB +2.70%’s Mark Zuckerberg had the best year of all billionaires. The 31-year-old added $11.2 billion to his fortune and moved up to No. 6 from 16. He and Amazon’s Jeff Bezos both make their first appearance in the top ten of FORBES’ annual ranking of the world’s wealthiest. Another first: A billionaire from China’s mainland, Wang Jianlin, whose company owns AMC Theaters and soon will own Legendary Pictures, has climbed into the top 20.